I am planning to do a tour around the San Juan and Gulf Islands in June and would really prefer to wing it as far as the itinerary goes. Problem is, everything I've read makes it sound like the campgrounds (at least on San Juan is.) fill up and reservations are needed. My experience in the past in CA/OR/WA has been that any campground with hiker/biker sites will always have room for a couple more. Is this the case on the Islands, or do I really need to bite the bullet and make reservations?